A
THERE’S no animal that symbolisesrainforest diversity quite as spectacularly as the tropical butterfly. Anyonelucky enough to see these creatures flitting between patches of sunlight cannotfail to be impressed by the variety of their patterns. But why do they displaysuch colourful exuberance? Until recently, this was almost as pertinent aquestion as it had been when the 19th-century naturalists, armed only withbutterfly nets and insatiable curiosity, battled through the rainforests. Theseearly explorers soon realised that although some of the butterflies’brightcolours are there to attract a mate, others are warning signals. They send outa message to any predators: “Keep off, we’re poisonous.”And because wearingcertain patterns affords protection, other species copy them. Biologists usethe term “mimicry rings”for these clusters of impostors and their evolutionaryidol.
B
But here’s the conundrum. “Classicalmimicry theory says that only a single ring should be found in any onearea,”explains George Beccaloni of the Natural History Museum, London. The ideais that in each locality there should be just the one pattern that bestprotects its wearers. Predators would quickly learn to avoid it and eventuallyall mimetic species in a region should converge upon it. “The fact that this ispatently not the case has been one of the major problems in mimicryresearch,”says Beccaloni. In pursuit of a solution to the mystery of mimeticexuberance, Beccaloni set off for one of the megacentres for butterflydiversity, the point where the western edge of the Amazon basin meets the foothillsof the Andes in Ecuador. “It’s exceptionally rich, but comparatively wellcollected, so I pretty much knew what was there, says Beccaloni.”The trick wasto work out how all the butterflies were organised and how this related tomimicry.”
C
Working at the Jatun Sacha BiologicalResearch Station on the banks oftheRio Napo, Beccaloni focused his attention ona group of butterflies called ithomiines. These distant relatives of Britain’sCamberwell Beauty areabundant throughout Central and South America and theCaribbean. They are famous for their bright colours, toxic bodies and complexmimetic relationships. “They can comprise up to 85 per cent of the individualsin a mimicry ring and their patterns are mimicked not just by butterflies, butby otherinsects as diverse as damselflies and true bugs,”says Philip DeVries ofthe Milwaukee Public Museum’s Center for Biodiversity Studies.
D
Even though all ithomiines are poisonous,it is in their interests to evolve to look like one another because predatorsthat learn to avoid one species will also avoid others that resemble it. Thisis known as Miillerian mimicry. Mimicry rings may also contain insects that arenot toxic, but gain protection by looking likes a model species that is: anadaptation called Batesian mimicry. So strong is an experienced predator’savoidance response that even quite inept resemblance gives some protection.“Often there will be a whole series of species that mimic, with varying degreesof verisimilitude, a focal or model species,”says John Turner from theUniversity of Leeds. “The results of these deceptions are some of the mostexquisite examples of evolution known to science.”In addition to colour, manymimics copy behaviours and even the flight pattern of their model species.
E
But why are there so many different mimicryrings? One idea is that species flying at the same height in the forest canopyevolve to look like one another. “It had been suggested since the 1970s thatmimicry complexes were stratified by flight height,”says DeVries. The idea isthat wing colour patterns are camouflaged against the different patterns oflight and shadow at each level in the canopy, providing a first line of defenceagainst predators.”But the light patterns and wing patterns don’t match very well,”hesays. And observations show that the insects do not shift in height as the dayprogresses and the light patterns change. Worse still, according to DeVries,this theory doesn’t explain why the model species is flying at that particularheight in the first place.
F
“When I first went out to Ecuador, I didn’tbelieve the flight height hypothesis and set out to test it,”says Beccaloni.”Afew weeks with the collecting net convinced me otherwise. They really flew thatway.”What he didn’t accept, however, was the explanation about light patterns.“I thought, if this idea really is true, and I can work out why, it could helpexplain why there are so many different warning patterns in any one place. Thenwe might finally understand how they could evolve in such a complex way.”Thejob was complicated by the sheer diversity of species involved at Jatun Sacha.Not only were there 56 ithomiine butterfly species divided among eight mimicryrings, there were also 69 other insect species, including 34 day-flying moths anda damselfly, all in a 200-hectare study area. Like many entomologists beforehim, Beccaloni used a large bag-like net to capture his prey. This allowed himto sample the 2.5 metres immediately above the forest floor. Unlike manyprevious workers, he kept very precise notes on exactly where he caught hisspecimens.
G
The attention to detail paid off. Beccalonifound that the mimicry rings were flying at two quite separate altitudes.“Their use of the forest was quite distinctive,”he recalls. “For example, mostmembers of the clear-winged mimicry ring would fly close to the forest floor,while the majority of the 12 species in the tiger-winged ring fly high up.”Eachmimicry ring had its own characteristic flight height.
H
However, this being practice rather thantheory, things were a bit fuzzy. “They’d spend the majority of their timeflying at a certain height. But they’d also spend a smaller proportion of theirtime flying at other heights,”Beccaloni admits. Species weren’t stacked rigidlylike passenger jets waiting to land, but they did appear to have a preferredairspace in the forest. So far, so good, but he still hadn’t explained whatcauses the various groups of ithomiines and their chromatic consorts to fly informations at these particular heights.
I
Then Beccaloni had a bright idea. “Istarted looking at the distribution of ithomiine larval food plants within thecanopy,”he says. “For each one I’d record the height to which the host plantgrew and the height above the ground at which the eggs or larvae were found.Once I got them back to the field station’s lab, it was just a matter ofkeeping them alive until they pupated and then hatched into adults which Icould identify.”
Questions 1-5
.................................................................................
The reading Passage has seven paragraphs A-I.
Which paragraph contains the following information?
Write the correct letter A-I, in boxes 1-5 on your answer sheet.
NB You may use any letter more than once.
1 Criticism against flight height theory of butterfly
2 Explained why Beccaloni carried out research in Ecuador,
3 Different mimicry ring flies at different height
4 The method of catching butterfly by Beccaloni
5 Not all Mimicry patterns are toxic information sent out from insects.
Questions 6-11
................................................................................
Do the following statements agree with the information given in Reading Passage1?
In boxes 6-11 on your answer sheet, write
TRUE if the sataement agrees with the information
FALSE if the statement contradicts the information
NOT GIVEN if there is no information on this
6 All butterflies’colours of wings reflect the sense of warning to otherpredators.
7 Insects may imitate butterflies’wing pattern as well.
8 Flying Altitude of butterfly is determined by their food.
9 Beccaloni agreed with flight height hypothesis and decided to reassure its
validity.
10 Jatun Sacha has the richest diversity of breeds in the world.
11 Beccaloni has more detailed records on the location of butterfly collectionthan
others.
Questions 12-13
.............................................................................
Choose the correct letter, A, B, C or D
Write your answers in boxes 12-13 on your answer sheet.
12 Which is correct about butterflies flight altitude ？
A Flight height theory already established
B Butterfly always flies at a certain height
C It is like the airplane’s flying phenomenon
D Each butterfly has its own favorable height
13 Which is correct about Beccaloni next investigation after flight height?
A Some certain statistics have already been collected
B Try to find connections between larval height and adult ones
C It’s very difficult to raise butterfly larval
D Different larval favors different kinds of trees
答案：
1. E 2. B 3. G 4. F 5. D
6 FALSE A段倒数第3行
7 TRUE C段倒数第3行
8 NOT GIVEN 无食物决定的相关信息
9 FALSE F段第一行
10 NOT GIVEN 无richestdiversity相关信息
11 TRUE F段末尾
12 D H段第三行
13 B I 段第三行
原文：
A
Sometimes ideas just pop up out of the blue. Or in Charlie Paton’s case, out of the rain. “I was in a bus in Morocco traveling through the desert,” he remembers. “It had been raining and the bus was full of hot, wet people. The windows steamed up and I went to sleep with a towel against the glass. When I woke, the thing was soaking wet. I had to wring it out. And it set me thinking. Why was it so wet?”
B
The answer, of course, was condensation. Back home in London, a physicist friend, Philip Davies, explained that the glass, chilled by the rain outside, had cooled the hot humid air inside the bus below its dew point, causing droplets of water to form on the inside of the window. Intrigued, Paton-a lighting engineer by profession-started rigging up his own equipment. “I made my own solar stills. It occurred to me that you might be able to produce water in this way in the desert, simply by cooling the air. I wondered whether you could make enough to irrigate fields and grow crops.”
C
Today, a decade on, his dream has taken shape as giant greenhouse on a desert off Abu Dhabi in the Persian Gulf-the first commercially viable Version of his seawater greenhouse. Local scientists, working with Paton under a license from his company Light Works, are watering the desert and growing vegetables in what is basically a giant dew-making machine that produces fresh water and cool air from sum and seawater. In awarding Paton first prize in a design competition two years ago, Marco Goldschmied, president of the Royal Institute of British Architects, called it ‘a truly original idea which has the potential to impact on the lives of millions of people living in coastal water-starved areas around the world.
D
The design has three main parts (see Graphic). The greenhouse faces into the prevailing wind so that hot, dry desert air blows in through the front wall of perforated cardboard, kept wet and cool by a constant tickle of seawater pumped up from the nearby shoreline. The evaporating seawater cools and moistens the air. Last June, for example, when the temperature outside the Abu Dhabi greenhouse was 46°c, it was in the low 30s inside. While the air outside was dry, the humidity in the greenhouse was 90 percent. The cool, moist air allows the plants to grow faster, and because much less water evaporates from the leaves their demand for moisture drops dramatically. Paton‘s crops thrived on a single litre of water per square metre per day, compared to 8 litres if they were growing outside.
E
The second feature also cools the air for the plants. Paton has constructed a double-layered roof with an outer layer of clear polythene and an inner, coated layer that reflects infrared light. Visible light can stream through to maximise photosynthesis, while heat from the infrared radiation is trapped in the space between the layer, away from the plants.
F
At the back of the greenhouse sits the third element, the main water-production unit. Just before entering this unit, the humid air of the greenhouse mixes with hot, dry air from between the two layers of the roof. This means the air can absorb more moisture as it passes through a second moist cardboard wall. Finally, the hot saturated air hits a condenser. This is a metal surface kept cool by still more seawater-the equivalent of the window on Paton‘s Moroccan bus. Drops of pure distilled water from on the condenser and flow into a tank for irrigating the crops.
G
The greenhouse more or less runs itself. Sensors switch everything on when the sun rises and alter flows of air and seawater through the day in response to changes in temperature, humidity and sunlight. On windless days, fans ensure a constant flow of air through the greenhouse. ‘Once it is tuned to the local environment, you don’t need anyone there for it to work’says Paton.We can run the entire operation off one 13-amp plug, and in future we could make it entirely independent of the grid, powered from a few solar panels. ’
H
The net effect is to evaporate seawater into hot desert air, then recondense the moisture as fresh water. At the same time, cool moist air flows through the greenhouse to provide ideal conditions for the crops. The key to the seawater greenhouse‘s potential is its unique combination of desalination and air conditioning. By tapping the power of the sun it can cool as efficiently as a 500-kilowatt air conditioner while using less than 3 kilowatts of electricity. In practice, it evaporates 3000 litres of seawater a day and turns it into about 800 litres of fresh water---just enough to irrigate the plants. The rest is lost as water vapour.
I
Critics point out that construction costs of £25per square metre mean the water is twice as expensive as water from a conventional desalination plant. But the comparison is misleading, says Paton. The natural air conditioning in the greenhouse massively increases the value of that water. Because the plants need only an eight of the water used by those grown conventionally, the effective cost is only a quarter that of water from a standard desalinator. And costs should plummet when mass production begins, he adds.
J
Best of all, the greenhouse should be environmentally, friendly. ‘ I suppose there might be aesthetic objections to large structures on coastal sites’says Harris,‘but it is a clean technology and doesn’t produce pollution or even large quantities of hot water.’
Questions 27-31
Do the following statements agree with the information given in Reading Passage 3? In boxes 27-31 on your answer sheet, write
TRUE if the statement agrees with the information
FALSE if the statement contradicts the information
NOT GIVEN if there is no information on this
27. Paton came up with the idea of making water in desert by pure accident.
28. The bus Paton rode in had poor ventilation because of broken fans.
29. Paton woke up from sleep to discover that his towel was wet.
30. Paton started his greenhouse project immediately after meeting up with his friend.
31. Paton later opened his own business in the Persian Gulf.
Questions 32-36
Complete the diagram below using NO MORE THAN THREE WORDS from the passage.
Questions 37-40
Complete the summary below using NO MORE THAN TWO WORDS from the passage
Write your answers in boxes 37-40 on your answer sheet.
The greenhouse Paton built is installed with37___to keep the air flowing if the wind stands still, and it is expected in the future to rely on electricity provided solely by 38___. Despite the high construction costs compared to desalination plants, the plants grown in Paton‘s greenhouse need much less water, and if produced in large quantities the 39___could be reduced remarkably. In addition to all these advantages, it is also40___, because it is clean and pollution free.
答案：
27. YES
【原文参考依据-A段首句】Sometimes ideas just pop up(突然出现) out of the blue(出其不意). Or in Charlie Paton's case, out of the rain. by accident 偶然
28. NO
【原文参考依据-A段第3行】‘it had been raining and the bus was full of hot, wet people. The windows steamed up(布满水汽) and I went to sleep with a towel against the glass.
题目说ventilated是很通风的意思，可是文章第一段第三行说了：the bus was full of hot
29. YES
【原文参考依据-A段倒数2-3行】The windows steamed up and I went to sleep with a towel against the glass. When I woke, the thing was soaking wet. I had to wring it out.
30. NOT GIVEN
30文章没有出现有关信息呢
27-30题，定位A段，
31. NO
【原文 参考依据-C段首句】Today, a decade on, his dream has taken shape as a giant greenhouse on a desert island off Abu Dhabi in the Persian Gulf- the first commercially viable version of his 'seawater greenhouse'.
题中的immediately与句中的decade形成反义关系
32. hot dry air
【原文参考依据-D段3-4行】The front of the greenhouse faces into the prevailing wind so that hot dry air blows in through a front wall.
32题，注意图表的观察，D段第三行中的blows in through体现了图中的动态，所以32题为hot dry air。
33. moist
【原文参考依据-D段4-5行】The wall is made of perforated cardboard kept moist by a constant trickle of seawater pumped up from ocean. 题中空格前remain与文中D段第四行kept替换，所以答案moist。
34. heat
【原文参考依据-E段倒数第二句】This combination ensures that visible light can stream through to the plants, maximizing the rate of plant growth through photosynthesis but at the same time heat from the infrared radiation is trapped the space between the layers, and kept away from the plants.
35. condenser
【原文参考依据-F段4-5行】The condenser is a metal surface kept cool by still more seawater. \\ Drops of pure distilled water flow into a tank for irrigating the crop.
36. pure distilled water
【原文参考依据-F段末句】Drops of pure distilled water form on the condenser and flow into a tank for irrigating the crops.
35题，没有pure 可以，但在符合字数限制，符合语法的状况下，都添会更好。
37. fans
【原文参考依据-G段5-6行】On windless days, fans ensure a constant flow of air through the greenhouse.
38. solar panels
【原文参考依据-G段末句】'we can run the entire operation off one13-amp plug, and in the future we could make it entirely independent of the grid, powered from a few solar panels.'
39. construction costs
【原文参考依据-H段首句】Critics point out that construction costs of around $4 a square foot are quite high.
$4 a square foot 的意思是：一平方英尺4美元
40. environmentally-friendly
【原文参考依据-末尾】Besides it really suggests an environmentally-friendly way of providing air conditioning on a scale large enough to cool large greenhouses where crops can be grown despite the high outside temperatures.
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